Jack



Jan. 22, 1935. s. MANDL Er AL JACK Filed April 12, 1933 4 Sheets-Sheet 2Q, QS n NQ Jan. 22, 1935. s. MANDL ET AL 1,988,601

JACK

Filed April 12, 195s @sheets-sheet 3 Jan. 22, 1935. s. MANDL ET AL JACKFiled April 12, 1933 4 sheets-Shen 4 Patented Jan. 22, .19.35

JACK

Sigmund Mandi and Edward M. Hauser, Mu-

waukec, Wis., assignors to Blackhawk Mfg. Co., Milwaukee, Wis., acorporation of Wisconsin -Application April 12, 1933, Serial No. 665,675

ing jacks and is particularly concerned with jacks' used around garages,repairshops and the like for raising one end of an automobile and sup- 5porting the same in elevated position. Obviously, however, such jackshave other uses.

One of the principal objects of the present invention is the provisionof a lifting jack which is of small height so that the jack can be movedunder very low objects, such as extremely low automobile axles, and canthen be actuated to raise the load to a considerableheight.

In the modern automobile of the type manufactured today, the axles arequite low, due to the general trend of providing a low center of gravityand a relatively small road clearance, and the modernautomobile also isgenerally equipped with extremely low fenders and aprons set aconsiderable distance ahead of or from the axles. In order to raise thecar it is preferable, of course, to engage the axle, and in order to dothis the jacks used for lifting and moving cars must, flrst` of all, below enough-to be moved in under and clear all overhanging parts and,moreover, must below enough so as to engage the low hung axles or otherportions of the automobile by which the latter is lifted. l

Another object of the present invention is the provision of a jack ofthis type in which the height of the lift is relatively great, beinghigh enough to elevate the automobile to a considerable height and alsoto engage and lift automobiles of older types .wherein the axles are ata greater height above the ground.

Briey, the present invention contemplates the provision of a jacklhaving the above mentioned low height high lift features and whereinthe lifting member is in the form of a lifting arm of the cantilevertype in which there is a long arm for lifting the load and a short armto receive the application of power. As is obvious, the longer thelifting varm the greater the height, and the shorter the power arm thelower to the oor ythe jack can be built. 'I'hat is to say, the shorterthe -power arm the lower the fulcrum or pivot point of the cantileverlifting member can be positioned.

Mechanical floor jacks for automobiles and the like are usually arrangedfor manual operation, and in this case where a relatively short powerarm is employed, it is necessary to provide for the greater powerrequired where the power arm is relatively short. The present inventionmeets these requirements by providing an improved form of reduction gearwhereby, while accommodating manual operation, suillcient power isdeveloped to enable the jack to raise the heaviest automobile. Theprovision of such reduction means forms therefore, another of theimportant objects'ofV the present invention..

More specically, another object of the present invention, with a view ofproviding an extremely low lifting jack, is the provision of a frame orequivalent supporting means for the jack wherein the fuleriun or pivotpoint for the lifting arm is l low and wherein the upper edges of theframe are substantially straight and horizontal, that is vto say, thefulcrum for the lifting arm is disclosed adjacent the upper horizontaledge of the jack frame, but is not materially higher, to facilitatemoving the jack into position under low overhanging parts of the car. Insome lifting jacks of the prior art, the fulcrum is disposed on acasting or the equivalent which extends to a point substantially abovethe upper edges of the side frame plates, and' this fulcrum supportfrequentlycollides with portions of the car body when an attempt is madeto move the jack underneath the car. Under such conditions the jack ispractically useless. Such disadvantages and objections are avoided inthe present construction.

Another object of the present invention is the provision of a liftingjack wherein a relatively great amount of power, required for swinging along lifting arm by means of a relatively short power arm, is obtainedin a simple and convenient construction embodying `mechanical partswhich are compact and simple in construction and appearance.

Still further, another object of the present invention is the provisionof longitudinally disposed parts, specifically, relatively movablehorizontally disposed racks with an interposed floating pinion, forsecuring the` aforesaid reduction. In addition, another object is theprovision of parts particularly adapted to resist the reactionsestablished in the development of such power.

Another object of the present invention is improved means forcontrolling the raising and lowering mechanism, which controlled meansis designed as a relatively low compact and simple unit enclosed bysuitable housing means and disposed 'at the end of the frame oppositethe lifting member.

Still further, another object of the present invention is the provisionof means securing an extral reduction between the operating handle andthe lifting member, which extra reduction is secured by parts which aredisposed and which operate e'lciently in a horizontal position on theJack frame. by virtue of which construction-theheightoftheiackabovethefioorisnotincreased by. the provision of meanssecuring the extra reduction.

nxrther, another object of the presentinventionhastodowiththedesignoftheraising'and lowering mechanism.According to the principlesofthepresentinventionthestressesinvolvedintheliftingoperationareimposedon parts designed to take suchstresses and in such a manner that as much eccentricity is avoidedaspossible. Inthisway.thestressesimposedareimposeddirectlyonthepartsconcerned.with the result thatthereislittlelikelihoodofthe operating mechanism getting out of line and.likewise. other maladiustments are avoided.

These and other objects of the present invention will be apparent fromthe following description of an illustrative structure in which theprinciples of the present invention have been embodied, in connectionwith the accompanying drawings illustrating such embodiment.

In the drawings:

Figure 1 is a side elevation of a lifting jack embodying the principlesof the present invention and showing the position of the lifting memberin elevated position in dotted lines;

rieure s is a section taken substantially suoni;Y

the line 5-5 of Figure 3;

Figureisanenlargedsectiontakenthrough the foot operated speed-up m forquickly elevating the lifting member up into contact with its load:

Figure 7 is a section taken along the line 7-7 of Figure 6:

Figure8isasectiontaken-alongtheline8-8 of Figure 2, but on a somewhatsmaller scale;

lifting-member also includes a relatively short powerarml.Itwillthusbeseenthatthearms ldandlcomprisealiftingbellcrankatthe outerend of which' the saddle 15 is pivotally to pivotally connect the linkor lifting arm 16 with the saddlemember 15.

In order to maintain the saddle in horizontal position a pair of linksare pivotally connected, as at 22, with the frame 11 at each sidethereof, the links also being pivotally connected, as at 23, with anextension of the saddle member 15.` The links 20, in connection with therelatively long lifting arm 16, constitute parallel link vmechanism.'I'he position of these parts in Figure 1 in which the referencenumerals have been applied to them is the lowered position, and it willbe noted that the lowered position of the saddle member 15 issubstantially at the level of the front supporting wheels 13. It willalso be noted that the frame 11 is so formed that its upper edge issubstantially horizontal and that the fulcrum support 17 does not extendany material extent above the upper edge of this member. Likewise. theposition of the saddle 15, when lowered, is substantially in the samehorizontal plane as the fulcrum 17. This, aswill vbe observed. providesa lifting jack in which the fulcrum 17 is-low enough to clear alloverhanging skirts, fenders, aprons, and other body parts of theautomobile when disposing thesaddle member 15 underneath the axle orsome other part of the car to be raised.

' With the advent of tires of large cross-section, popularly known atthe present time as air wheels, and with the advent of stream lining andlow hung body parts, the provision of a lifting jack in which thefulcrum 17 is quite close to the floor is extremely important. Lookingat Figure 1, for example, it will be observed that the jack can be usedand can be inserted under any low load under which the saddle member 15can itself be dis- Flgures 9 to `12, inclusive, are viewseorrespondposed ing to Figure 2 and showing the slidable reversing platein its different positions; kand Figure 13 is an enlarged sectional viewshowing the rotatable saddle for engaging and supporting the load.

Referringnow to the drawings, particularly Figure l, the illustratedlifting lack in which the principles ofthe present invention have beenembodied comprises a front or lifting yend 10 disposed at the front ofan elongated frame l1 and lifting mechanism enclosed within a housing 12at the opposite end of the frame 11 from the lifting end 10. -Thehousing 12 preferably forms a part of the frame 11 and the whole, as

' a unit, is supported on wheels 13 and 14. 'I'he 'stud 17 which iscarried by the frame 11 adiacent the horizontal upper edge thereof, andthe One of the means securing this result is, as mentioned above, theprovision of the relatively short power arm 18. By power arm is meantthe portion of the bell crank 16-18, to which force is applied to raisethe saddle member l5. In view of the fact that older types of carsemployed axles having considerably greater road clearance, and also inview of the fact that it is sometimes desirable to be able to raise oneend of the automobile to a considerable height, it is necessary that thelifting arm 16 be of substantial length in order to obtain therequiredlifting range. As a result of these two factors, it will be observedthat the construction involves or requires means capable of exerting arelatively great amount of force on the power arm 18 in order to be ableto conveniently and quickly handle the load. The present inventioncontemplates means capable of exerting a considerable force, in fact, amuch greater force for this purpose than the lifting jacks of the priorartrof which we are aware. Y

',Ihe lowermost end of the power arm 18 carries a pivot pin 30 to whichis pivotally connected a thrust bar or member 31 which extends, as willbe seen from Figure 1, rearwardly and slightly upwardly. Referring nowto Figures l3 and 4, it

will be observed that this. thrust membercomprisesapairofthrustrodsorbarsSBdisposed substantially centrally ofthe frame 11 and terminating rearwardly at a point where the bars 33 areapertured to receive a pin or shaft 35 onwhich a floating pinion 36 isdisposed. The floating pinion is enclosed within the housing 12, andthis housing is also formed with bosses or flanges 38 between which isdisposed stationary reaction members or abutment bars 39 and astationary rack` 40 having teeth 41 with which the teeth of the oatingpinion- 36 mesh. As will be seen from Figure 8, the pinion 86 isdisposed between the two stationary reaction bars 39 and that the bars33 are, at their rearmost ends, disposed in contact with the lower edgesof the reaction bars 89.

'Ihe housing or casing 12 is formed of two sections and 46, separablealong the line 47, so as to facilitate properly machining the casingparts and also to facilitate assembling the raising and loweringoperating mechanism.

The lower housing section 46 forms the bottom of the casing 12 and isprovided4 with a longitudinally extending elevated portion 50 which isformed to provide ways 51 and guiding flanges 52 (Figures 4 and 8) forslidably receiving a longitudinally shiftable rack member 55. This rackmember is meshed with the floating pinion 36, as best shown in Figure 3,and from this figure it will be seen that if thelrack bar is shifted,tothe left in Figure 3, for example, the pinion 36 will be caused toroll along the relatively stationary rack 40, thus advancing the thrustbars 33 ata rate which is equal to half the peripheral velocity of thepinion 36 at its lower portion, which corresponds, of course, with therate of movement of the slidable rack 55.

By virtue of this construction, it will be observed that the rackmembers 40 and 55 are disposed in a horizontal position and that thepinion 36 is relatively small so that the overall height of these partsis small. Nevertheless, by virtue of this construction alone, a two toonereduction is provided. 'I'he stationary rack 40, which isapproximately only one-half the length of the rack 55 but of the sametooth form, is secured in the upper part of the upper housing section 45by means of pins or the equivalent disposed in suitable openings in thebosses 38. 'I'hese pins are also utilized as the supporting means forthe reaction bars 39.

Since the rear ends of the bars 33 are in contact with the reaction bars39 and since the bars 33 are disposed in the downwardly and forwardlyinclined position, it will be seen that the reaction thrust of the loadon the saddle member 15,` acting through the bell crank 16--18, causesthe upper ends of the bars 33 to bear against the reaction bars 39. Inthis way the pinion 36 is relieved of all such strain, the contactbetween the thrust bars 33 and the reaction bars 39 serving, therefore,to maintain the pinion 36 in proper position with respect to theY rack40 with which it meshes. Likewise, the pinion 36 is maintained in properposition with respect to the slidable rack 55. If desired, the pinion 36may be designed with teeth that bottom in the rack 40 so as to take thevertical reaction, in which case' the bars 39 may be omitted.

Any known means may be provided for shifting the slidable rack 55, butin this type of lifting jack it is desirable that, whatever the meansemployed, such means should not have an excessive over-all height butshould be low with respect to the supporting surface. In the preferredform of the present invention ratchet mechanism is provided for shiftingthe rack 55, and preferablyy this ratchet mechanism includes a pinionmesh- Y i ing with the rack 55, which pinion is identical, for allpractical purposes, with the pinion. 36. Since these pinions are of thesame tooth form, the construction and manufacture is greatly simpliedsince the portion of the rack which en,- gages the pinion 36 and theportionwhich engages the ratchet pinion, later to be described indetail, can be formed in one and the same rack. The jack can thus bemade,at less cost since duplicate parts can be employed.

The ratchet mechanism will now be described. The upper section of thehousing 12 is formed with bosses 61 at either side thereof, and thesebosses rotatably receive a pinion shaft 63 which extends at both endsthrough the housing'orcasing section and which is provided with asquared portion 64 intermediate the inner ends of said bosses, as bestshown in Figures 4 and 5. The pinion referred to above as beingidentical with or of the same tooth form as the pinion 36 is indicatedby the reference numeral 66 and is either mounted on or provided with asleeve portion 67 which includes a square opening adapted to be mountedon the squared portion 64 of the pinion shaft 63 in a non-rotatablerelation. Obviously,

polygonal forms other than squared portions may be employed for thispurpose. The teeth of the pinion 66 mesh with the teeth of the rack bar55,

the pinion 66 beingdisposed closely adjacent the pinion 36, as bestshown in Figures 2 and 3, so as to allow the use of a relatively shortrack 55.

At one side, the teeth or other portions of the pinion 66 are extended,as indicated by the reference numeral 70, and these extended portionsare' received. within the hub portion 74 ofl a ratchet wheel 75 providedwith ratchet teeth 76. The

ratchet wheel 75 is mounted on one end of the for limited oscillationabout an axis concentric with the axis of the ratchet wheel by aswinging quadrant disposed within the upper section 45 of the housing12. The quadrant is indicated in its entirety by the reference numeral80 and, as best shown in Figures 4 and 5, the quadrant 80 includeslaterally spaced arm portions 81 and 82 provided with suitable bearingportions 84 and 85, thelatter portion being mounted directly on one endof the sleeve 67 of the pinion 66 while the bearing portion 84 of thequadrant 80 is journaled for rotation on the hub portion 74 of theratchet wheel 75. It will be noted from Figures 4I and 5 that all ofthis mechanism is assembled within a narrow compass and all parts areenclosed by the housing or casing 12.

75 is provided in a form of driving pawl means carried The driving pawlmeans proper is indicated by extended outwardly through a slot 100, asindicated in Figure 4, and are joinedytogether by a connecting portion102 having a plurality of openings 103-formed therein in which 'suitablemanually operated means is adaptemto be engaged. The portions of thearms 81 and 82 which are extendedV upwardly are connected together by atransversely disposed web portion 105, best shown in Figures 3 and 4.The connecting portion 102 of the quadrant is extended in a generallyfore and aft direction so as to practically cover the slot 100 in thehousing 12. The connecting portion 102 is also 4extended laterally forthe same shown in Figures 4 and 5. The intermediate portion of the yoke111 is disposed closely adiacent the apertured connecting portion orhead.

102 of the quadrant 80, and suitable plunger means 118 is slidablycarried by the handle 110 and is adapted to be engaged in any one of theopenings 103 formed in the exterior portions of the quadrant 80. Theplunger 118 is provided with a shoulder 119 engageable with one of thewebs 120 of the handle 110 to limit the inward movement of the plunger,118. A spring 123 or the equivalent may be provided for biasing theplunger 118 for movement toward engaging position with the-quadrant 80.

A cover -125 is providedfo'r enclosing the shiftable rack soV as toprevent the operator and other persons or objects from coming intocontact with this rack. `The Acover 125 comprises a rectangularsectionhaving a lower open side 126 and an upwardly curved tongue 127 whichl iscurved. as best shown in Figure 3, to correspond with the curvature ofthe upper section 45 of the casing. The tongue 127 is also arranged tobe disposed underneath the apertured head 102 of the quadrant 80 and inbetween the lateral arm portions 81 and 82 thereof, as best shown inFigure 4. At its end, the tongue 127 of the rack cover 125 is suitablythreaded to receive an attaching screw 129 or the equivalent. Obviously,any other means for mounting theA rack cover 125 in position on thecasing or housing 12 may be provided if desired.

As will be clear from the above description,-

the plunger 118 of the handle 110 may be engaged in any of the openingsor slots 103. Vertical oscillations of the handle 110 will then beeffective for turning the ratchet wheel by virtue of the engagement ofthe driving pawl 91 with, the teeth 76. In `this construction it isnecessary to provide some means for holding the ratchet wheel againstretrograde rotation. Such means .may conveniently take the form of a;

holding pawl 130 mounted upon a fixed pawl pinion shaft 131 suitablypinned or otherwise mount- Ied in a boss 132 provided in the lowersection 46 of the casing 12. A spring 133 or the equivalent serves tohold the pawl 130 up against the teeth 76 of the ratchet wheel 75.

Swinging the handle downwardly in the direction of the arrow shown inFigure 2 will cause the driving pawl 91 to engage one of the teeth ofthe ratchet wheel and will therefore rotate the pinion 66 by virtue ofthe direct connection between the ratchet wheel 75 and the pinion.

In this connection itis important to note that `no torque is transmittedthrough the pinion shaft 63. During rotation of the ratchet wheel 75 inthe direction of the arrow, the teeth 76 will ride over the holding pawl130, but the latter is biased forl movement into engagement therewithand will therefore serve to hold the ratchet wheel 75 in any position offorward advance. Rotation of the pinion 66 serves to shift the slidablerack member 55 toward the left as viewed in Figures 2 and 3 and willroll the oating pinion 36 toward the left along the fixed rack 40.Thus,` the thrust member 33 will be-advanced to swing the lifting arm 16upwardly, the extent of movement of the thrust member 33 being one-halfthe extent of. movement of the rack 55.

It is important to note that both the driving pawl 91 and the holdingpawl 130 are disposed underneath the ratchet wheel 75. By virtue of thisconstruction the overall height of the rear end of the Jack is -keptdown to a desirable minimum. As will be apparent from the abovedescription, vertical oscillations of the handle 110 will cause, first,the pawl 91 to engage one of the teeth 76 on the ratchet wheel 75 sothat as the handle 110 is swung downwardly the ratchetI wheel 75 will beadvanced. and next the pawl will be engaged with one of the teeth 76 tohold the ratchet wheel in that position against retrograde movementwhile the handle 110 is swung upwardly, the driving pawl now idly-ridingover the teeth 76 to its new position of engagement with the ratchetwheel 75. Upon a second downward movement of the handle 110 the ratchetwheel will again be advanced. In this manner an intermittent forwardrotation will be imparted to the ratchet wheel 75 so that the shiftablerack 55 will cause the thrust member 31 to be advanced toraise the loadsupported on the saddle 15.

In mechanism of this sort itis, of course, necessary to provide somesort of means for reversing theabove operations so that the saddle 15and the load supported thereon may be lowered under the control of theoperator. Such means will now be described.

A reversing plate is slidably suported on the upper casing part 45 bymeans of pins 151 disposed within slots 152 formed in the reversing late150. The slidable reversing plate 150 is provided with a plurality ofcam portions 155 and .156 which are adapted to engage, respectively,with projecting studs 159 and 160 formed on or carried by the holdingand driving pawls 130 and 91, respectively, whereby the reversing plate150 can control the driving and holding pawls. A spring 161 is anchoredto one end of the reversing member 150 and to a stud 162 carried by thecasing 12 and serves'to continuously bias the reversing member 150 forforward movement, which is toward the left as viewed in Figures 2 and 9to 12, inclusive.

When the ratchet mechanism is to be actuated to raise the lifting member16, it is necessary to hold the reversing member 150 out of contact withthe lugs 159 and 160 on the holding and lifting pawls and against thetension of the spring 161. Means forv performing this functionpreferably takes the form of a lockout member 165, comprising a shaft166 carrying a locking arm 167 at one end and an operating pedal 168 atthe other end, as best shown in Figures 2 and 5.V The locking arm 167 isprovided with a stud 170 disposed in the plane of the reversing plate150, as best shown in Figure 5, and this locking stud is adapted tocooperate with a third cam ber 150.

section 171 formed on the rea portion of the reversing plate 150 andbein `=f 4the form shown in Figures 2 and 9 to 12. This third camsection is recessed, as at 172 and 175 in Figures 2, 10 'and 11, toaccommodate both the engaged and released positions of the locking stud170.

When the locking arm shaft 166 is rocked rearwardly, the locking stud170 contacts -with the rear portion 171 of the reversing plate 150, thelatter having the portion 175 cut away to accommodate the releasedposition of the locking stud 170. 'I'his swinging movement of the arm167 moves the reversing plate 150 against the tension of the spring 161from a position, such as that shown in Figures 11 and 12, to theposition indicated in Figure 2 in which the cam sections 155 and 156 areentirely free of the lugs or studs 159 and 160 on the holding andlifting pawls. In this position the locking stud 170 moves into thecurved recess 172 to effectively lock the cam plate 150 in retractedposition. When the holding and driving pawls are thus released from thecontrol of the plate 150, oscillations of the handle 110. serve toadvance the ratchet 75 to raise the lifting saddle 15 as describedabove. It is important to note that as long as the reversing member 150is held in its,inoperative or rearward position, see Figure 2, theoscillations of the pawls 9 1 and 130 are not interfered with.

When it is desired to lower the lifting saddle 15, the'locking shaft`166 is rocked forwardly, that is, toward the left asviewed in Figure 2,this motion, first moving the locking plate 150 rearwardly slightlyuntil the stud 170 enters the space 175 at the rear end of the reversingmem- Actually, as soon as the stud 170 has cleared the curved recess172, the spring 161 becomes immediately effective to shift the reversingmember 150 forwardly, carrying with it the locking arm 167 and movingthe same to the position indicated in Figure 9. In this position theholding pawl will be sustaining the load on the ratchet so that whilethe spring 161 will throw y the reversing plate forwardly and up againstthe lug 159 the strength of the spring 161 is not sumcient to -forciblymove the holding pawl 130 out of engagement from the ratchet teeth.Thus, the reversing member 150 is merely moved up against the stop lug159 on the holding pawl 130 and it remains in that position until thehandle is swung downwardly slightly so as to cause the driving pawl 91to engage one of the ratchet teeth and to rotate the ratchet wheelslightly. This will take the load oi! the holding pawl 130 and as soonas the load is released from the holding pawl, the spring 161 shifts thereversing plate 150 to its forwardmost position, and this movement, byvirtue of the cam portion engaging the lug 159 on the holding pawl 130,swings the ment of the reversing member 150; however. will move the camsection 155 away from-the' holding pawl 130 which will then move intoengagement with one of the ratchet teeth on the ratchet wheel 75.asindicatedinFigure 11. Assoonas the holding pawl is fully engaged withthe ratchet teeth -it will then take the load cn the ratchet, therebyrelieving the driving pawl 91 of the load so that lug on the drivingpawl will no longer be effective to shift the reversing member 150against its spring 161, the latter then shifting the high point of thecam section 156 past the lug 160, which'throws the driving pawl 91entirely out of engagement with the ratchet wheel 75. as shown in Figure12.

The partsare soarrangedmssho'wninll'igure 11, that the reversing member150 is moved by the lug 160 on the driving pawl for some distancerearwardly of the lug 159 on the holding pawl before the latter is fulLvengaged with the ratchet wheel and before it takes the load of theratchet wheel from the driving pawl. At the instant, ofcourse, that theholding pawl takes the load and the driving pawl is released, the spring61 snaps the'reversing member 150 forwardly, as mentioned above, fromthe position indicatedinFigure lltothatshowninFlgure 12 in which the camsection 155 is drawn into abutting engagement with the lug 159 on theholding pawl 130. This movement of the reversing member 150 shifts thedriving pawl 91 out of engagement with the ratchet wheel, by virtue ofthe cam section 156 acting against the lug 160 on the driving pawl 91.The reversing member 150 moves forwardly to the position shown in Figure12 in which the lug 160 on the driving pawl 91 engages a dwell portionof the cam section 156. 'Ihls is the extent of upward movement of thehandle 110.

The next step is to shift the handle 110 downwardly, at which time thedriving pawl 91 will be held out of engagement with the ratchet teeth byvirtue of the lug 160 moving along the dwell portion of the cam section156 so that the lifting or driving pawl 91 will be shifted forwardly toa newV position before engaging one of the ratchet teeth on the ratchetwheel 75. As soon, however, as the lug 160 engages the inclined portionof the cam section 156 the driving pawl 91 will be moved bythe spring 95upwardly into engagement with the next ratchet tooth, or some otheradvanced tooth, dependingvupon the length of the cam section 156 and theamount the cam member 150 moves rearwardly of the lug 159 during upwardmovement of the handle 110, and then a slight additional downwardmovement of holding pawl 130 away from the ratchet wheel ,f the handle110 will transfer the load from the 60 75. which is the position shownin-Figure 10.

As soon as the holding pawl 130 is released and is positively held outof engaging position with respect to the ratchet wheel 75, the liftinghandle may be raised to let the load lower, the driving pawl 91 beingengaged with the ratchet wheel 75 and sustaining theload. During thismovement the driving pawl 91 moves with the ratchet wheel 75, thismovement being in the direction of the arrow shown in Figure 11 and iscontinued until the lug 160 on the driving pawl 91 engages the secondcam portion 156 of the reversing member 150, see Figure 11. At thistime, since the load is sustained by the driving pawl, the continuedupward movement of the handle will cause the holding pawl 130 again tothe driving pawl 91, at which time the holding pawl 130 will then bereleased by virtue ofthe spring 161 acting to shift the reversing member160 to its forwardmost position, this operation being indicated inFigures 9 and 10, and the sequence described above will then berepeated.

It is important to note that, by virtue of the sliding cam reversingmember 150 and by virtue of the positioning of the driving and holdingpawls, as well as the locking member, in the lower portion of the casing12 and substantially underneath the ratchet wheel 75, a construction isprovided wherein the overall height is kept down to a desirable minimum.

- ribs on the interior thereof.

l casing 12.

Reference has been made above to the fact that the casing 12 consists oftwo separable sections 45 Yand 46. Preferably, the lower section'46 isdetachable from the upper section and is removably secured thereto bystud bolts 180. Preferably, these bolts are disposed in suitable bossesformed on the upper and lower casing sections. Preferably, also, thesesections have reenforcing The casing sections 45 and 46 are preferablyin the form of castings and are provided at their forwardA ends withreduced portions 183 to receive the rear end of the frame section 11.Preferably, although not necessarily, this section is also a casting andis provided with suitable flanges or the like arranged to be secured tothe casing 12 by cap screws 185 or the equivalent. By virtue of thisconstruction, it is a relatively-simple matter to remove the lowercasing section 46 to obtain access to the operating mechanism. It willbe observed that certain of the operating mechanism is mounted on thelower section while other parts are mounted on the upper section. Thisarrangement is desirable. in that the assembly of the two sets ofoperating parts is materially facilitated and the parts are disposed inproper relation when .the casing sections are joined together. 1

As will be clear from the above descriptio one oscillation of the handlemoves the ratchet wheel through only one or' at least only a few ratchetteeth, this being necessary in order to develop the power required toraise comparatively heavy loads. It is therefore desirable to providesome form of speedup mechanism for quickly raising the saddle 15 up tothe point where it begins to engage the load. v`Such mechanism is shownin Figures 5, 6 and 7 and is attached directly to the pinion shaft 63.This speedup mechanism includes a pedal or operating member 200pivotally connected, as by a pivot pin 201, with a rotatable casingr203supported for oscillation on the extended end 204 of the pinion shaft63. The rotatable casing 203 encloses a toothed wheel 206 which ispinned, asiat 208, onto the pinion shaft 63 and isV rotatable therewith.'I'he operating arm 200 is provided with a nose 211 which is adapted, inone position,

relative to the casing 203, to engage with one of the teeth on the wheel206. Normally, however, the arm 200 is held away from engagement withthe toothed wheel 206 by virtue of a spring 212 disposed in a socket 213formed in the arm 200 and reacting against a shoulder 215 formed on therotatable casing 203.l f

The casing 203 is supported on the pinion shaft 63 for limitedoscillation relative thereto and relative to the jack frame, beingconnected by spring means 216 with a boss 217 formed on the Theoperating arm 200 and the casing 203 are both, asa unit, mounted forpivotal movement with respect to the frame or casing 12. Preferably, thespring means 216 has one end 220 extended into the rotatable casing 203while the other end is received withinV a suitable opening in the boss217 on the casing 12.

The strength of the spring 216 is greater than the strength of thespring 212, so that whenever pressure is applied to the operating arm200 in the direction of the arrow shown in Figure 7, the spring 212 iscompressed which allows the nose 211 to engage one of these teeth on thewheel 206. This engages the arm 200 with the wheel 206 so that furtherpressure on the 'arm swings the casing 203, the toothed wheel 206 andthe pinion shaft 63. This, as will be obvious, rotates the pinion 66 andthe ratchet wheel '75 associated therewith and advances the slidablerack 55 to quickly raise the saddle 15 into engagement with the load tobe lifted. Rotation of the pinion 66 also causes rotation-of the ratchetwheel 75, lbut the rotation thereof in this direction is permitted byvirtue of the. ratchet teeth riding over both the driving pawl 91 andthe holding pawl 130, as will be clear from Figure 2.

While we have described above the structure in which the principles ofthe present invention are preferably embodied, it is to be understoodthat our invention is not to be limited to the specific details shownand described, but that, in fact, widely different means may be employedin the practice of the broader aspects of our invention.

What we claim, therefore, and desire to secure by Letters Patent is 1.In a jack, an elongated frame, a lifting member shiftable generallyvertically thereon, a rack slidable onsaid frame, ratchet mechanism forshifting said rack relative to the frame, and means connected betweensaid rack and said lifting member for securing substantially a two toone ratio therebetween.v

2. In a jack, an elongated frame, a lifting member including a bellcrankhaving a relatively short arm, a power applying member connectedvat one end with said arm, a pinion journaled near the other end of saidpower applying member, a rack fixed to said frame, a second rackslidable longitudinally thereof, said pinion being in mesh with anddisposed between said racks, and means for moving said second rack toshift said pinion and said power applying member attached thereto.

3. In a jack, an elongated frame, a lifting member shiftable generallyvertically thereon, a rack slidable on said frame, ratchet mechanism forshifting said rack relative to the frame, a second rack mountedv on saidframe above the first rack, a floating pinion mounted for rollingmovement between said racks, and a thrust bar having journal meansreceiving said pinion and connected .with said lifting member.

4. In a jack, an elongated frame, a lifting member shiftable generallyvertically thereon, a rack slidable on said frame, ratchet mechanism forshifting said rack relative to the frame, a stationary rack carried .bysaid frame above said firstv rack, a pair of abutment bars disposed onopposite sides of said stationary rack, a floating pinion mountedbetween said racks, a thrust rod connected with said pinion and withsaid lifting member, and ratchet mechanism disposed rearwardly on saidlifting frame for shifting said slidable rack, said thrust rod reactingagainst said abutment bars.

5. In ajack, an elongated frame, a lifting member shiftable generallyvertically thereon, a rack slidable on said frame, ratchet mechanism forshifting said rack relative to the frame, and including .a pinionjournaled in said framel and disposed in mesh with said rack, a secondrack `xedly mounted on said frame adjacent said slidslidable on saidframe, ratchet mechanism for shifting said rack relative to the frame,andincluding .a pinion journaled in said frame and disposed in mesh withsaid rack, a second'rack xedly mounted on said frame adjacent saidslidable rack, a'floating pinion having the same tooth form :is saidfirst pinion and'meshingwith both of said racks, said pinions being` ofthe same size and disposed closely Vadjacent one another when thefloating pinion is adjacent the rear end of said xed end, and a thrustrod reacting against said frame and adapted to receive the first pinionto transmit lifting force to said lifting member. l

7. In a jack, an elongated frame comprising spaced side plates havingsubstantially horizontal upper edges, a lifting member mounted betweensaid side plates at one end of the frame for pivotal movement about alow fulcrum point and having a forwardly extending lifting arm and arelatively short downwardly extending power arm, a load receiving saddlecarried at the outer end of said lifting arm, a rack bar slidablycarried by the frame between said side plates, ratchet and pinion meansfor shifting said rack bar, a second rack bar fixedly carried by 'saidframe above said first rack bar, a floating pinion disposed between saidrack bars and in mesh therewith, and a downwardly and forwardlyextending thrust bar connected at its forward end with said power armand carrying said pinion at its rear end.

8. In a jack, raising and lowering means including a shaft and auxiliarymeans for operating the same including a member movably mounted on saidshaft, and an operating member extendving beyond said first member inpower receiving position and movably mounted on said first member andhaving a releasable connection with said shaft for rotating the sameindependently of the operation of said raising and lowering means.

9. In a jack, raising and lowering means including a shaft, andauxiliary means for operating the same including a toothed wheel fixedto the shaft, a support pivotally mounted on the shaft adjacent saidwheel, and a lever pivotally mounted on said support for movementrelative thereto into and out of engagement with said toothed wheel andoperative during said engagement to impart rotation to both said supportand said shaft.

10. In a jack, an elongated frame, a lifting member at one end thereof,a longitudinally disposed thrust rod connected with said member, a rack.bar operatively connected with said thrust rod for shifting the same,a'pinion meshing with said rack bar, a ratchet wheel separated from butdisposed in direct engagement with said pinion, and means for drivingsaid ratchet wheel.

11. In a jack, an elongated frame, a lifting member at one end thereof,a longitudinally disposed thrust rod connected with said member, a rackbar operatively connected with said thrust rod for shifting the same, apinion meshing with said rack bar, a shaft on the frame supporting saidpinion, a ratchet wheel having a hub 'portion directly engaging theteeth of said pinion for rotating the same, and means for driving saidratchet wheel.

12. In a jack, an elongated frame, a lifting `member at one end thereof,a longitudinally disposed thrust rod connected with said member, a rrackbar operatively connected with said thrust rod for shifting the same, apinion meshing with said rack bar, a shaft on the frame and extendingtherefrom at oneend, said pinion being nonrotatably supported on saidshaft, a ratchet wheel v having means directly engaging portions of saidpinion for drivingthe same, pawl means for driving said ratchet wheel,and auxiliary meanson said. shaft for driving the pinion independentlyof said ratchet wheel and pawl means.

13. In a jack, a lifting member, lifting mecha- I .nism including ashiftable ratchet ymember and holding and lifting pawls for raising saidlifting member, a slidable reversing member, means biasing saidreversing member for movement in Eone direction, and releasable lockingmeans for said reversing member, the latter being adapted for raisingsaid lifting member and operative inv another position to control saidpawls to provide for lowering said lifting member, and means forshifting the position of said reversing member.

15. In a jack, an elongated frame, a lifting member at one end of saidframe, raising andI lowering mechanism at the other end includinglongitudinally movable rack means operatively connected with saidlifting member, a housing enclosing said mechanism, a ratchet wheelassociated with said rack, lifting andl holding pawls disposed on thelower side of said ratchet wheel and in longitudinally spaced relation,a reversing cam member slidablir mounted on the frame longitudinallythereof and adapted to be shifted into operative engagement with saidpawls to provide for lowering the lifting member, said pawls, ratchetwheel and cam member being mounted in the lower portion of said housing,a quadrant supported on said frame for pivotal movement about the axisof said ratchet wheel, said quadrant having an opening formed thereinand said lifting pawl being carriedy by the quadrant and positionedbelow the opening therein, and means engageable in said opening forshifting said. quadrant.

16. In a jack, an elongated frame, a lifting member at one end thereof,a longitudinally disposed operating member connected with the liftingmember, a slotted housing near the other end of said frame, raising andlowering mechanism disposed within said housing and connected with saidoperating member and including a part extending from the housing throughthe slot therein, and an operating handle movably mounted exteriorly ofthe housing and having means engageable with said extended part of theraising and lowering mechanism.

1'7. In a jack, an elongated frame, a lifting member at one end thereof,a longitudinally disposed operating member connected with the liftingmember, a slotted housing near the other end of said frame, said housingcomprising upper and lower sections, raising and lowering mechanismdisposed within said housing and connect ed with said operating member,one of said housing sections being detachable to facilitate assembly ofsaid raising and lowering mechanism, and means disposed in the slot insaid housing for operating said raising and lowering means.

18. In a jack, an elongated frame, a lifting ing the nrst member formovement toward a given position about its-exis of movement, and

member at one-end thereof. a longitudinally disposed operating memberconnected with the lifting member, a slotted housing near the other endof said frame, raising and lowering mechanism disposed within saidhousing land con` nected with said operating member and including alongitudinally shiftable member extending from said housing, and acover. for said shiftable member carried by said housing and ineluding apart disposed in the slot in the housing.

19. In a jack, an elongated frame, a lifting member at one end thereof,a longitudinally disposed operating member connected with the liftingmember, a slotted housing near the other end of said frame, raising andlowering mechanism disposed within said housing and connected with saidoperating member, said mechanism includf ing an operating member'havinglaterally spaced portions extending through the slot in said housing anda longitudinally shiftable member extending from said housing, and acover for said shiftable member carried by said housing and including apart disposed in the slot in the housing between the laterally Ispacedportions of said 20. In a jack, raising and lowering cluding a shaft, anauxiliary means for operating `the shaft including a` member movablymounted on the frame, means carried by said member and having anoutwardly extending force receiving end disposed outwardly of saidmember andan inner end disposed adjacent said member and adapted torotate the shaft in one direc- 4cluding a shaft, an auxiliaryv means foroperating the shaft including a member mounted forv limited motion aboutthe axis of said shaft, a second member movably mounted on said ilrstmember and adapted in. one position to be operatively connected with theshaft to rotate the same and,l

in another position to be releasedv from operative means inengagementwith the shaft, spring means biasbiasedmeansresctingagainstsaidnrstmemberandservingtoholdseidsecondmemberinsaidinoperativeposition.

22. Inaisck ,raisingandiowering meansincludingashaft. anauxiliary-meansfor operat- -ing theshaft including a member movably mounted withrespect to the frame labout the `axis of said shaft, a'y second membermovably mounted on. said ilrst memberand adapted in one position to beoperatively engaged with said shaft and in another position to be out ofoperative engagement therewith, means biasing said. first member formovement to a given position, and biasingmeans acting between said firstand second-members for holding the latter in a given position withrespect to the first member, said rst biasing means being stronger thansaid second biasing means, whereby when said second member is operatedthesecond biasing means is overcome and said second member is initiallymoved into operative engagement with said shaft, additional movementimparted to said second member serving to shift both the shaft and saidfirst member. I

'23. In a jack, a frame, a lifting member, raising and loweringmechanism including a ratchet member and lifting and holding pawlsdisposed on the lower side of said ratchet member adjacent one another.a slidable reversing member carried by the frame and operative in oneposition to free said pawls to provide for raising said lifting memberand operative in another potion to control said pawls to provide forlowering said lifting member, spring means biasing said member. formovement in one direction, and lock-- ing means for holding saidreversing member in another position against the bias of said springmeans. v

BIGMUND `MANDL. EDWARD M. PFAUBER.

